426 4-spd Swap

Discussion of the 426 Street / Strip HEMIs.

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dmc8163
Posts: 6
Joined: Wed Mar 04, 2009 2:16 pm

426 4-spd Swap

Post by dmc8163 » Thu Mar 05, 2009 1:47 pm

Hi,

I'm new to this forum and appreciate any help you can provide. I have "inherited" Hemi clone project. It is a 1970 Challenger. With it came a 426 and 4-spd. I completed the front end and the Dana rearend and have installed the motor in the engine bay. I went to buy the flywheel and clutch assembly. I thought I had an 18-spline A833 4-spd. I thought all Hemi's were 18-spline. Anyway, I counted the splines and actually have a 23-spline transmission.

Can I use a 23-spline trans with a 426 Hemi?

I should add that I can't tell you much about the motor. There is nothing on the pad and no VIN. The block has the numbers 2468330-M and 7623 on the right side.

The trans has the numbers C956642 Z, 11-25, and C99589.

If a 23-spline can be used do they make 8-bolt 23 spline flywheel? How many teeth should it have?

Sorry for the 20 questions. I would just like to avoid having to buy another tansmission.

Thanks, Dave

mart
Posts: 536
Joined: Tue Mar 22, 2005 2:06 pm

Re: 426 4-spd Swap

Post by mart » Thu Mar 05, 2009 7:09 pm

dmc8163 wrote:Hi,

I'm new to this forum and appreciate any help you can provide. I have "inherited" Hemi clone project. It is a 1970 Challenger. With it came a 426 and 4-spd. I completed the front end and the Dana rearend and have installed the motor in the engine bay. I went to buy the flywheel and clutch assembly. I thought I had an 18-spline A833 4-spd. I thought all Hemi's were 18-spline. Anyway, I counted the splines and actually have a 23-spline transmission.
Can I use a 23-spline trans with a 426 Hemi? I should add that I can't tell you much about the motor. There is nothing on the pad and no VIN. The block has the numbers 2468330-M and 7623 on the right side. The trans has the numbers C956642 Z, 11-25, and C99589.
If a 23-spline can be used do they make 8-bolt 23 spline flywheel? How many teeth should it have? Sorry for the 20 questions. I would just like to avoid having to buy another tansmission.

Thanks, Dave
=============================
A factory Hemi 4 speed instalation would have used an 18 spline input shaft and clutch disk.
There's no reason though that you can't use a 23 spline tranny. Just use a 23 spline clutch disk to match the tranny and it'll all bolt up. As far as the flywheel goes, there's no such thing as a "23 spline flywheel"! Your 8 bolt hemi flywheel won't know or care whether the clutch disk you attach to it has 18 or 23 splines. About your block. A blank pad and no VIN indictes the engine (or block) was originally sold over the counter or was a warrenty replacement piece. Hope this helps.

mart
===================================================================

dmc8163
Posts: 6
Joined: Wed Mar 04, 2009 2:16 pm

Re: 426 4-spd Swap

Post by dmc8163 » Fri Mar 06, 2009 2:04 pm

Mart,
Thank you very much. Duh. I did finally figure out the flywheel thing. I have been told that the 23-spline is a small block tranny and not strong enough for a stock build 426. Do you a disagree with them? I am also confused about what size to buy, 10", 10.5", 11" or 11" "scalloped." What is the correct size? I really appreciate your help. Dave

mart
Posts: 536
Joined: Tue Mar 22, 2005 2:06 pm

Re: 426 4-spd Swap

Post by mart » Sat Mar 07, 2009 5:32 pm

dmc8163 wrote:Mart,
Thank you very much. Duh. I did finally figure out the flywheel thing. I have been told that the 23-spline is a small block tranny and not strong enough for a stock build 426. Do you a disagree with them? I am also confused about what size to buy, 10", 10.5", 11" or 11" "scalloped." What is the correct size? I really appreciate your help. Dave
------------------------------------------------
The 23-spline tranny "theoritcally" is not as strong as the 18-spline
"Hemi" 4-speed, but the difference in actual strength is only marginal.
Unless you're going to pound the car exteremly hard all the time, I
doubt you'll notice any real difference in durability.The 23-spline tranny
was used in the small block 318 and 340 cars, but it was also the
standard 4-speed used in *most* 383 and 440 powered Mopars as well.
A few special 'non-Hemi' cars - like the 440 six-pack powered Road
Runners, GTXs, Super Bees etc - did offer the 18-spline "Hemi
4-speed" as an option, usually also in conjunction the "Hemi-spec"
Dana 60 rearend as well, as part of a Drag Pack package. But like I
said, unless you're going to really pound the car and subject it to a
near constant diet of drag racing, you should be fine with a 23-spline
tranny. About clutches. Again, it depends exactly what you plan to do
with the car, but for street use, a stock replacement type 23-spline,
11 inch (10.95 in. actually) clutch disk along with either a standard
'heavy-duty' replacement or a stock 'Hemi-spec' pressure plate
should suffice. One more note too. I'm not sure what bellhousing you're
using - a standard 383-440 bell, or the correct "Hemi" bell. If
you're using the Hemi bell, all you need to do to use the 23-spline
tranny is swap the standard 4.35 o.d. front collar/bearing retainer
for the bigger 4.80 o.d." Hemi" front collar and use the matching,
also larger diameter, Hemi throw-out bearing. If your bell is
originally from a B or RB 'non-Hemi' car, simply use the standard
23-spline tranny's 4.35 diamiter front collar and throw-out
bearing.
mart
===============================================================

dmc8163
Posts: 6
Joined: Wed Mar 04, 2009 2:16 pm

Re: 426 4-spd Swap

Post by dmc8163 » Sun Mar 08, 2009 9:57 am

Mart, I'm most grateful for your reply. I was really agonizing over having to buy an 18-spline trans. Trust me, no one is going to beat on this car if I ever get it done. I will go out and start measuring the bearing retainer. I haven't been able to figure out what bell housing I have. I'll try to find photos of each type online. As soon as I get the bearing retainer question sorted out I'll order all the parts. Do you have a vendor that you recommend? I was thinking Brewer or YearOne. Thanks, Dave

dmc8163
Posts: 6
Joined: Wed Mar 04, 2009 2:16 pm

Re: 426 4-spd Swap

Post by dmc8163 » Sun Mar 08, 2009 11:16 am

Mart,
I inpected the bellhousing and transmission and took some measurements. The number on the bellhousing is 2892262. The trans hole is 4,80". The bearing retainer is 4.80" and has number C99369. The bearing "sleeve" is 1.25" and the shaft is 1.00". I'm ok to go with what I have, correct? Thanks, Dave

mart
Posts: 536
Joined: Tue Mar 22, 2005 2:06 pm

Re: 426 4-spd Swap

Post by mart » Mon Mar 09, 2009 3:34 am

dmc8163 wrote:Mart,
I inpected the bellhousing and transmission and took some measurements.
The number on the bellhousing is 2892262. The trans hole is 4,80". The
bearing retainer is 4.80" and has number C99369. The bearing "sleeve"
is 1.25" and the shaft is 1.00". I'm ok to go with what I have, correct?
Thanks, Dave
-----------------------------------------

Good deal! It sounds like you've got everything well under control! You have
the"big hole" Hemi bell and the tranny already has the matching "Hemi style"
front collar swapped on to it. All you should need now to complete the set up
is a 23-spline clutch disk to match the inpit shaft on the tranny. Ya' gotta'
post some pics of this beast as it goes together...and some more pics
of the car once its completed!

mart
=======================================================

dmc8163
Posts: 6
Joined: Wed Mar 04, 2009 2:16 pm

Re: 426 4-spd Swap

Post by dmc8163 » Mon Mar 09, 2009 7:54 pm

Thanks mart,

I'll post photos as soon as I figure out how to do it.

Back to neverending questions. I was feeling very comnfortable that I had the ability to do this. But my manuals state that i should align the clutch housing face and the bore. I've read the directions and looked at the diagrams and still don't get it. Is it really necessary? I have a dial indicator and metal base but I don't have the special tool that installs in the pilot bearing. Are there other places that have directions?

Hopefully this will be the last "bump" in the road. :)

Dave

mart
Posts: 536
Joined: Tue Mar 22, 2005 2:06 pm

Re: 426 4-spd Swap

Post by mart » Thu Mar 12, 2009 11:40 pm

dmc8163 wrote:Thanks mart,

I'll post photos as soon as I figure out how to do it.

Back to neverending questions. I was feeling very
comnfortable that I had the ability to do this. But my
manuals state that i should align the clutch housing
face and the bore. I've read the directions and looked
at the diagrams and still don't get it. Is it really
necessary? I have a dial indicator and metal base
but I don't have the special tool that installs in the
pilot bearing. Are there other places that have
directions?

Hopefully this will be the last "bump" in the road. :)

Dave
------------------------------------------
I doubt it's necessary to go to the trouble of alligning the
bell to the center of main bearing bores in the block with
a dial indicator. That's something you *might* want to do
if you were building an all out "professional class"' race
motor (like for a fuel dragster or somthing!) - particuculary
one that uses all kinds of custom made or aftermarket parts
- like a non-production, aftermarket block fitted to an
aftermarket scattersheild, clutch can or adaptor , that *may*
or *may not* have been properly machined, matched (or even
intended!) to go together! That's when you've got to start
checking and verifying everything. For most everything else,
using mostly stock parts, the factory tolerences will be ok.
Remember that Mother Mopar built the Street Hemi cars on
the same regular assembly line as everything else they built.
On the assembly line, bells and the otherwise completed Hemi
engines came down the line and were screwed together in
whatever random order the that parts happened to arrive at
that point on the line. Nobody bothered measuring , matching
or custom machining the bells to the blocks. The only real thing
to check is that the stock dowell pin that aligns the bell to the
the block is still there and that is clean and not damaged.
(The same goes for the hole in the bell that fits over the dowel pin
too) if all checks out ok, I'd just put the bell on, tighten the bolts
and go.

One thing you might want to do that will make installing and
lining up the cllutch disk easier, is to get a spare input shaft
from a junk tranny and use that as an "alignment tool" to
center the clutch disk on the flywheel. Put the disk on the
flywheel face and instal the pressure plate, but only tighten
the bolts finger tight. Then, with the disk loosely sandwiched
between the pressure plate and the flywheel, use the
spare input sfaft to center the clutch disk to the pilot bearing
in the end of the crank. Then, with the spare input shaft
holding the clutch disk in place, torque the the pressure
plate bolts to spec and remove the input shaft. Now, when
you're ready to instal the tranny, the clutch disk will already
be centered and the tranny should just slide in place. It's a heck
of lot easier to do it this way than lying under the car and
trying to line up the clutch disk by manouvering and finessing
a a heavy, bulky tranny around!

One last thing. Hardwear and small stuff is cheap. To save
trouble and aggrivation later, spend a few bucks now for
the little stuff that often gets overlooked. Use new, proper
flywheel and pressure plate bolts, a new pilot bearing and new
throw-out bearing. Make sure the clutch fork is in good
shape and that it's not bent or damaged in any way .Ditto for
the pivot ball that the clutch fork rides on too. Also, make sure
the flywheel surface is rust-free, smooth and unmarked, that
its not burned or glazed and is dead square. If there's any
question at all about the condition, spend a few bucks and
have it resurfaced. For what extra it'll cost for the little stuff
to do things right, it's not worth chancing stuff that's old or in
any way questionable! When doing a clutch, do it right....and
you'll only do it once! :)

mart

P.S. Almost forgot. Yyou asked about the "special tool" for
installing the pilot bearing.I just use a scrap input shaft (the
same one I use for aligning the clutch disk) with the gear cut
off and cut down so it's just a short stub about 3 inches long.
Place the new pilot bearing over the nose of the input shft,
center it in the end of the crank and then press it into the
hole by *gently* tapping on the end of the input shaft with
a hammer. You know how to remove an old pilot bearing
from a crank too, right? Fill the hole in the pilot bearing with
wheel bearing grease. Then, take the same cut-down input
shaft as above, place the nose of the shaft into the grease
filled hole in the pilot bearing and hit the shaft with a hammer.
Each time you hit the shaft and force it a little deeper into the
hole, the grease being non-compressable, gets behind the pilot
bearing and forces the bearingt out of the crank

===========================================================

dmc8163
Posts: 6
Joined: Wed Mar 04, 2009 2:16 pm

Re: 426 4-spd Swap

Post by dmc8163 » Fri Mar 13, 2009 8:56 am

Thanks Mart. That is all wonderful information and I will follow all the advice. I've still to determine if the crank has a pilot bearing in it. It looks like there is styrafoam in it where the bearing goes. I'm still having trouble with what clutch to order. One vendor sells a 10 1/2" clutch set, and another has an 11" set. I haven't found a 10.95 clutch set. If you recommend a specific clutch set from a specific manufacturer I'm all ears. :) Thanks, Dave

If you can access my email address from my profile please email me and I'll send you car pics.

Dave

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